Dubgaill

The Dubgaill, meaning "dark foreigners" in Gaelic, were a group of Danish Vikings who arrived in Ath Cliath (Dublin), Ireland in 851. They were named for their black shields, and they were rivals with the Norwegian Finngaill Vikings, who had arrived decades earlier and were distinguished by their white shields. Upon arriving at Ath Cliath in 851, the Dubgaill made a great slaughter of the Finngaill, and the rivalry persisted until around 941.